<!DOCTYPE html>
<script src="../resources/text-based-repaint.js"></script>
<script>
    onload = runRepaintAndPixelTest;
    function repaintTest() {
        document.getElementById('elm').style.background = 'green';
    }
</script>
<div id="container" style="columns:3; column-gap:0; column-fill:auto; width:500px; height:500px; writing-mode:vertical-rl;">
    <div style="width:100px;">
        <div id="elm" style="width:1500px; background:yellow;"></div>
    </div>
</div>
<p>Test changing the background color of a big block that overflows the flow thread.</p>
<p>A green square should be seen above.</p>
